In general, there is great interest in developing and implementing improved BESS controllers that are capable of directing the inverters of energy storage systems (ESSs) to dispatch active and reactive power in a manner that benefits a distribution system and a utility. This involves three important functions: 1) photovoltaic (PV) station capacity firming, 2) voltage support, and 3) energy time shift. PV station capacity firming involves suppressing large power swings that could potentially harm utility generation units. Voltage support involves providing a tighter voltage band across a feeder on which an ESS is installed. Voltage support also aims to reduce feeder voltage regulator tap changes, leading to an increase in regulator life. Finally, energy time shift involves performing peak load shaving by storing energy at times when cost is low and discharging energy at feeder peak load times. Thus, what is still needed in the art is a new way in which a grid tied BESS can be controlled and used.
What is also still needed in the art is a BESS controller that handles dispatching active power based on input data streams from a feeder on which the BESS is installed. The controller should dispatch the BESS' energy based on the daily fulfillment of two main BESS functions together. The performance of these two functions should be optimized in parallel. The first function is renewables capacity firming (RCF), where the intermittent power of a renewable energy station (photovoltaic or wind) is conditioned to become fairly stable or non-intermittent. The second function is peak load shaving (PLS), where the controller optimizes battery energy during the performance of RCF to be able to dispatch its full power capacity at the predicted feeder peak load time that is predicted by the controller from historical data. The controller should be completely unsupervised and should not require any human intervention for its operation. Real time data streams should allow the controller to perform smart decisions that contribute to value maximization for grid operators.